In R-3.1.1 on Linux and Windows I get:
zQR <- qr(matrix(exp(1i*cos(1:4)), 2, 2))
zQ <- qr.Q(zQR)
#Error in .Internal(qr_qy_cmplx(qr, as.matrix(y), FALSE)) :
# there is no .Internal function 'qr_qy_cmplx'
We expect it to not throw an error and that
crossprod(zQ, Conj(zQ)) - diag(nrow(zQ))
gives approximately the zero matrix.
It worked in R-2.15.2 but not in R-3.0.0.